If this is the response, what came before? Response All members of the Grypoceratidae have a ventral lobe with the exception of "Stenoporceras", "Parastenopoceras", and "Virgaloceras", which have a ventral saddle instead.
CONVERSATION:Conversation:
Person 1: What are the main types of grypoceratidae?
Person 2: Menuthionautilus" from the Lower Triassic has a rapidly expanding, smooth involute shell with a deep dorsal impression, broadly convex flanks and rounded venter, suture with a shallow ventral lobe and siphuncle positioned against the venter.
Person 1: What other types are discussed?
Person 2: " Gryponautilus" from the Upper Triassic is broadly involute with a narrowly rounded, keel-like venter at maturity and shallow ventral and lateral lobes in the suture.
Person 1: Are there any other interesting aspects about this article?
Person 2: 